Pickup trucks are designed for the transportation of cargo. They are often owned by tradesmen such as construction workers, plumbers, electricians, and farmers. These truck owners not only transport equipment to a job site but typically work with or install what they transport. In such applications a pickup truck is used not only as a means of transporting material, but also as a mobile shop, in which use the truck is required to store tools and small hardware items like screws, nails and fittings.
Cargo bed utility boxes have been developed for this purpose. Boxes have been manufactured of sheet metal, fiberglass and plastic of various types. Although a cargo bed utility box should meet basic functional requirements such as keeping the contents dry, organized and securely attached to the truck box, for many purchasers the appearance of the box is also important. For the tradesman the appearance of a vehicle may reflect on a reputation for neat high quality work.
Another type of pickup truck owner utilizes the truck for personal transportation during the week and utilizes cargo transporting capability for a second job or hobby on nights or on weekends. This type of pickup truck owner is inclined to apply the appearance standards of cars to a pickup truck, further highlighting the importance of the appearance of any accessory used with a truck.
Both types of pickup truck owners typically purchase a thermoplastic thermoformed bedliner either with the truck or as an aftermarket accessory. Bedliners protect the truck from scraping and wear from cargo carried in the truck. They also can prevent cargo items from sliding around within the cargo box.
Truck utility boxes are sometimes constructed of plastic. Plastic in addition to being readily formed to meet stylistic requirements has many advantages. It does not rust or corrode, it is lightweight, and can be fabricated into complex shapes at reasonable costs. In addition, plastic resists denting, does not require painting, and is not prone to damaging the truck box or truck box liner. Nevertheless, plastic has one disadvantage: its lower strength compared with other materials can lead to distortion where loads are concentrated. This is particularly a problem in attaching a lid support system and in developing a reliable latching system.
What is needed is a system for avoiding concentrated loads and the distortion which such loading can cause in plastic truck utility boxes.